Asuka, also known as ASTRO-D before launch and ASCA afterward, was a joint mission in which NASA and the Massachusetts Institute of Technology both provided spacecraft components in exchange for observation time with the orbiting telescope. The spacecraft operated normally for over seven years; however,

A solar flare on 14 July 2000 caused heating and expansion of the upper atmosphere, which increased the drag and external torque on ASCA. The attitude was perturbed, so the solar panels lost lock on the Sun, resulting in discharge of the batteries. ASCA reentered the atmosphere on March 2, 2001.